The invention discloses a device for simulating oral dissolution of a gum-base tobacco product. The device comprises a power device, a piston, a shell, the gum-base tobacco product, an upper oral cavity simulating system and a lower oral cavity simulating system, wherein the upper oral cavity simulating system is located on the upper half portion of the interior of the shell, the lower oral cavity simulating system is located on the lower half portion of the interior of the shell, the gum-base tobacco product is placed in a gap between the upper oral cavity simulating system and lower oral cavity simulating system, an upper saliva pool provided with an upper opening is arranged on the upper oral cavity simulating system, a lower saliva pool is arranged on the bottom of the shell, a saliva circulating pipe is arranged outside the shell, an upper pipe orifice of the circulating pipe is communicated with the upper saliva pool, a lower pipe orifice of the circulating pipe is communicated with the lower saliva pool, a circulating pump is arranged on the circulating pipe, and a collecting cup is arranged on the circulating pipe in a communicated mode. The device simulates the processes of chewing and salivary secretion of the gum-base tobacco product in the oral cavity, so that the actual using situation of the gum-base tobacco product is observed.